Gas phase growth of metal-organic frameworks on microcantilevers for highly sensitive detection of volatile organic compounds

A gas-phase technique, known as chemical vapor deposition of metal-organic frameworks (MOF-CVD), is used for sensitizing silicon cantilevers. These cantilevers are coated with a uniform and compact Zn(EtIm)2 (MAF-6) film, enabling the detection of volatile organic compounds (VOCs) through a change in the resonance frequency of the cantilever. The MOF-coated sensor exhibits remarkable sensitivity to VOCs within the 0.33–0.71 Hz/ppm range and a limit of detection (LOD) spanning from 4 to 9 ppb. Notably, these sensitivities surpass those achieved by ZnO-coated cantilevers by two orders of magnitude. This high sensitivity is attributed to the high porosity and large surface area of MAF-6. The approach employed in this work is compatible with conventional microfabrication techniques and offers an advantageous avenue for the development of highly sensitive gas sensors.